The average numbers of primary and tertiary amine groups in dendrimer materials were measured by acid-base titration. 聚酰胺-胺(PAMAM)是一种有着广泛用途的树形大分子,酸碱滴定分析可以表征合成的PAMAM中所含的伯胺基及叔胺基的数量,因此作为一种重要的辅助表征手段被PAMAM的合成及改性研究者所采用。
(ii) 4-methylcyclohexan-1-amine is a stronger base than p-toluidine. 104PRACTICE PROBLEM True or False: When 1,3-dimethylguanidine is protonated, its double-bonded nitrogen is the nitrogen that accepts the proton because the lone pair electrons on the other nitrogens are delocalized. 105PRACTI...
The catalytic activity was found to depend critically on the synthesis procedure, the nature and amount of metal species introduced and the spatial separation between the acidic sites and amine groups. DFT analysis of the reaction pathway indicates that, for weak Brnsted acid groups, such as Si ...
Hydroxylamine hydrochloride is a crucial synthetic intermediate utilized in the production of medicine and aromatic amine compounds, containing active hydroxyl groups and nitrogen atoms, so it has the ability to form complexes with various metal ions, making it a better metal complexing agent [28], ...
of amine and 86.5% yield of nitrile (3a) (Table1, entry 5). The time course of the synthesis of3aover amorphous MnOxdisplays a steep volcano curves for2a, indicating that the imine of2ais the reaction intermediate and could be hardly obtained in high selectivity via tuning of the reaction...
The high removal ability of materials obtained at 650 °C is attributed to cation exchange reactions between calcium and magnesium in aluminosilicates, ... STJ Bandosz - 《Journal of Colloid & Interface Science》 被引量: 99发表: 2006年 Nonlinearity of cationic aromatic amine sorption to alumin...
pulicaris, with significantly diverse species compositions, were resolved: well supported Estonian, Polish, Slovak and Radecz groups, and a weakly-supported Ambiguous group. The abundance of C. pulicaris was found to be positively correlated with the composition of the geographically-diversified plant...
More importantly, all the uncoordinated phosphoric acid groups are periodically aligned within the channels and display significantly enhanced acidity compared to the non﹊mmobilized acids. This facilitates the Brnsted acid catalysis of asymmetric condensation/amine addition and imine reduction. The enantio...
two carboxylate and one phosphonate groups of threeLand connect adjacent 2D sheets to form a 3D structure. There are two types of irregular 1D channels with maximal sizes of ~1.0 × 1.2 and ~0.8 × 1.0 nm2that are uniformly lined with Cr3clusters and hydrophobictert-butyl ...
The chemical reactivity of a set of borophosphines of the general formula R2B-G-PY2, where G is the connector group between the Lewis acidic site, a borane group, and the Lewis basic site, a phosphine fragment, is theoretically investigated through their Lewis acidity and Lewis basicity, as...